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Q26 (IAS/2019) Environment & Ecology › Pollution & Conservation › Energy and emissions Official Key

In the context of which one of the following are the terms 'pyrolysis and plasma gasification' mentioned?

Result
Your answer: —  ·  Correct: D
Explanation

The correct answer is option D: Waste-to-energy technologies.

Gasification, pyrolysis and plasma technologies heat waste materials to high temperatures, creating gas, solid and liquid residues.[2] Thermal treatment including pyrolysis, gasification, incineration, and plasma gasification is the most commonly employed technique for the generation of energy in different forms and waste-to-wealth.[3] Pyrolysis is a process that breaks down waste materials through heat without the presence of air, resulting in recyclable products such as char, oil, wax, and flammable gases.[4] These technologies are specifically used for converting waste materials into usable energy forms, making them integral to waste-to-energy conversion processes. They have no connection to rare earth element extraction, natural gas extraction, or hydrogen fuel-based automobiles, making options A, B, and C incorrect.

Sources
  1. [1] https://www.no-burn.org/wp-content/uploads/Gasification-Pyrolysis-and-Plasma-Incineration.pdf
  2. [2] https://www.no-burn.org/wp-content/uploads/Gasification-Pyrolysis-and-Plasma-Incineration.pdf
  3. [3] https://pubs.rsc.org/en/content/articlehtml/2025/ma/d5ma00449g
  4. [4] https://link.springer.com/article/10.1007/s43938-025-00079-8
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Q. In the context of which one of the following are the terms 'pyrolysis and plasma gasification' mentioned? [A] Extraction of rare earth e…
At a glance
Origin: Mostly Current Affairs Fairness: Low / Borderline fairness Books / CA: 0/10 · 10/10

This is a 'Confidence Check' question. 'Pyrolysis' is a standard static concept found in every basic Environment book (Shankar IAS, PMF) under Solid Waste Management. UPSC added the scarier-sounding 'Plasma Gasification' to intimidate you, but the answer was locked in the static syllabus.

How this question is built

This question can be broken into the following sub-statements. Tap a statement sentence to jump into its detailed analysis.

Statement 1
Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of extraction of rare earth elements?
Origin: Web / Current Affairs Fairness: CA heavy Web-answerable

Web source
Presence: 5/5
"Gasification, Pyrolysis & Plasma Incineration What are waste gasification, pyrolysis, and plasma treatment/disposal technologies? Gasification, pyrolysis and plasma technologies heat waste materials to high temperatures, creating gas, solid and liquid residues."
Why this source?
  • Explicitly names the three technologies including pyrolysis and plasma (as 'Gasification, Pyrolysis & Plasma Incineration').
  • Describes these technologies in the context of waste treatment/incineration, not rare earth element extraction.
Web source
Presence: 5/5
"Thermal treatment including pyrolysis, gasification, incineration, and plasma gasification is the most commonly employed technique for the generation of energy in different forms and waste-to-wealth"
Why this source?
  • Lists pyrolysis and plasma gasification together as thermal treatment methods used for waste-to-energy.
  • Context is urban waste and energy generation, not extraction of rare earth elements.
Web source
Presence: 4/5
"2.1 Pyrolysis Pyrolysis is a process that breaks down waste materials through heat without the presence of air, resulting in recyclable products such as char, oil, wax, and flammable gases"
Why this source?
  • Provides a definition and context for pyrolysis as a waste-to-energy/waste-management process.
  • Again the context is waste management/energy, with no mention of rare earth extraction.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Pyrolysis/Ga*ification > p. 293
Strength: 4/5
“Pyrolysis is a process of chemical decomposition of organic matter brought about by heat. In this process, the organic material is heated in the absence of air until the molecules thermally break down to become a gas comprising smaller molecules (known collectively as syngas). Gaeificatiorl can also take place as a result of partial combustion of organic matter in the presence of a restricted quantity of oxygen or air. The gas so produced is known as producer gas. The gases produced by pyrolysis mainly comprise carbon monoxide (z5olo), hydrogen and hydrocarbons (r5Yo), and carbon dioxide and nitrogen (6o70). The next step is to'clean'the syngas or producer gas.”
Why relevant

Defines pyrolysis as thermal decomposition of organic matter in absence of air and describes the syngas/char/liquid products produced by heat-driven breakdown.

How to extend

A student could extend this by checking whether similar thermal decomposition is used to break down mineral-bearing matrices or electronic waste to liberate rare earths.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.8 WASTE TO ENERGY > p. 294
Strength: 4/5
“In today's era, there are increasing quantities of waste due to urbanization, industrialization and changes in life patterns which are harmful to the environment. In the recent past, development of technology has helped to reduce the amount of waste for its safe disposal and to generate electricity from it. Waste-to-energy has the potential to divert waste from landfills and generate clean power without the emission of harmful greenhouse gases. This significantly reduces the volume of waste that needs to be disposed of and can generate power Pyrolysis and gasification are emerging technologies apart from the common incineration and biomethanation.”
Why relevant

States pyrolysis and gasification are emerging technologies used to process waste and generate useful products (waste-to-energy).

How to extend

One could reasonably investigate whether these waste-processing routes are applied to wastes that contain rare earths (e.g., electronic waste, monazite processing residues).

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.6 BIOMASS > p. 292
Strength: 3/5
“Biomass, on the other hand, releases carbon dioxide that is largely balanced by the carbon dioxide captured in its own growth (depending how much energy was used to grow, harvest, and process the fuel) Chemical processes like gasification, combustion and pyrolysis convert biomass to useful products. Combustion being the most common of them. Each of the technologies mentioned produces a major calorific end product and a mixture of by-products. The processing method is selected on the basis of nature.”
Why relevant

Explains gasification/pyrolysis as chemical processes that convert complex feedstocks (biomass) into useful products, showing these are general-purpose high-temperature conversion methods.

How to extend

Use this pattern to ask if the same high-temperature conversion concepts are adapted to mineral or ore processing for REE recovery.

Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 2: The Solar System > Plasma > p. 24
Strength: 4/5
“• Plasma is one of the four fundamental states of matter, the others being solid, liquid, and gas. It is ionised gas (atoms and molecules are converted into ions typically by removing one or more electrons from the outer shell).• Lightning and electric sparks are everyday examples of phenomena made from plasma.• Neon lights could more accurately be called 'plasma lights' because the light comes from the plasma inside of them.”
Why relevant

Defines plasma as an ionised, high-energy state of matter (ionised gas), implying plasma-based processes can provide high temperatures/energies.

How to extend

With basic knowledge that high temperatures can break down or melt materials, a student could test whether plasma gasification is used to treat mineral sands/residues to separate or free rare earth elements.

Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 9: Distribution of World Natural Resources > thorium > p. 40
Strength: 3/5
“Torium is a by-product of the extraction of rare earths from monazite sands. Torium was used for the breeding of nuclear fuel uranium. It is used as a nuclear fuel in aircraft engines. Torium is a very efective radiation shield. India's Kakrapara-1 reactor is the world's frst reactor which uses thorium. Australia, USA, and India have large deposits of thorium, followed by Canada, Brazil, South Africa and Turkey.”
Why relevant

Notes thorium is a by-product of extracting rare earths from monazite sands, identifying a specific mineral source and associated by-products.

How to extend

Combine this mineral-source fact with thermal/thermal-plasma processing clues to explore whether pyrolysis/plasma gasification are applied to monazite sands or their residues to recover REEs or separate thorium.

Statement 2
Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of natural gas extraction technologies?
Origin: Web / Current Affairs Fairness: CA heavy Web-answerable

Web source
Presence: 5/5
"Thermal treatment including pyrolysis, gasification, incineration, and plasma gasification is the most commonly employed technique for the generation of energy in different forms and waste-to-wealth"
Why this source?
  • Directly mentions both terms 'pyrolysis' and 'plasma gasification'.
  • Context of the passage is waste-to-energy/urban waste, not natural gas extraction, indicating these terms are used in a different context.
Web source
Presence: 5/5
"Gasification, Pyrolysis & Plasma Incineration What are waste gasification, pyrolysis, and plasma treatment/disposal technologies? Gasification, pyrolysis and plasma technologies heat waste materials to high temperatures, creating gas, solid and liquid residues."
Why this source?
  • Names 'Gasification, Pyrolysis & Plasma Incineration' and describes these as waste treatment technologies.
  • Shows these terms are presented in the context of waste management rather than natural gas extraction.
Web source
Presence: 4/5
"For example, in Connecticut, the industrial price of natural gas was US$5.88 per thousand cubic feet (MCF) in November 2019 and US$7.54 MCF−1 in March 2019, while in California, the price was US$7.16 MCF−1 in November 2019 and US$9.01 MCF−1 in March 2019"
Why this source?
  • Discusses natural gas (prices, industrial natural gas) but contains no mention of 'pyrolysis' or 'plasma gasification', showing a separation of contexts in the available sources.
  • Supports the point that passages about natural gas do not pair those terms with natural gas extraction technologies.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Pyrolysis/Ga*ification > p. 293
Strength: 4/5
“Pyrolysis is a process of chemical decomposition of organic matter brought about by heat. In this process, the organic material is heated in the absence of air until the molecules thermally break down to become a gas comprising smaller molecules (known collectively as syngas). Gaeificatiorl can also take place as a result of partial combustion of organic matter in the presence of a restricted quantity of oxygen or air. The gas so produced is known as producer gas. The gases produced by pyrolysis mainly comprise carbon monoxide (z5olo), hydrogen and hydrocarbons (r5Yo), and carbon dioxide and nitrogen (6o70). The next step is to'clean'the syngas or producer gas.”
Why relevant

Defines pyrolysis as thermal decomposition producing 'syngas' (a combustible gas mixture) — a general thermal route to produce gaseous fuels.

How to extend

A student could note that because pyrolysis produces syngas, they should check whether texts about natural-gas production or processing mention syngas or thermo-chemical conversion as alternative sources or upstream processes.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.6 BIOMASS > p. 292
Strength: 4/5
“Biomass, on the other hand, releases carbon dioxide that is largely balanced by the carbon dioxide captured in its own growth (depending how much energy was used to grow, harvest, and process the fuel) Chemical processes like gasification, combustion and pyrolysis convert biomass to useful products. Combustion being the most common of them. Each of the technologies mentioned produces a major calorific end product and a mixture of by-products. The processing method is selected on the basis of nature.”
Why relevant

States gasification and pyrolysis are chemical processes that convert biomass into useful gaseous products, establishing these terms as technologies that generate fuel gases.

How to extend

One could extend this by comparing the technologies that produce gaseous fuels (pyrolysis/gasification) with conventional natural-gas extraction to see if the same terminology appears in natural-gas technology discussions.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.8 WASTE TO ENERGY > p. 294
Strength: 3/5
“In today's era, there are increasing quantities of waste due to urbanization, industrialization and changes in life patterns which are harmful to the environment. In the recent past, development of technology has helped to reduce the amount of waste for its safe disposal and to generate electricity from it. Waste-to-energy has the potential to divert waste from landfills and generate clean power without the emission of harmful greenhouse gases. This significantly reduces the volume of waste that needs to be disposed of and can generate power Pyrolysis and gasification are emerging technologies apart from the common incineration and biomethanation.”
Why relevant

Lists pyrolysis and gasification as 'emerging technologies' in waste-to-energy contexts, linking the terms clearly to production of fuel gases from feedstocks other than fossil reservoirs.

How to extend

A student could infer these terms are commonly used in waste/biomass energy literature and then check natural-gas/extraction chapters to see whether such conversion processes are discussed there.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Types Of Hydrogen Based On Extraction Methods > p. 298
Strength: 5/5
“zz,to,z, Types Of Hydrogen Based On Extraction Methods Depending on the nature of its extraction, hydrogen is categorized into three categories, namely, grey, blue and green. • Grey Hydrogen: it is produced via coal or lignite gasification {black orbrown}, or via a process called steam methane reformation (SMR) of natural gas or methane (grey). These tend to be mostly carbon-intensive processes. • Blue Hydrogen: It is produced via natural gas or coal gasification combined with carbon capture. storage (CCS) or carbon capture use (CCU) technologies to reduce carbon emissions. . Green Hydrogen: It is produced using electrolysis of water with electricity generated by renewable energy.”
Why relevant

Explains 'grey hydrogen' can be produced via gasification or via steam-methane reformation (SMR) of natural gas — explicitly mentioning gasification in a context tied to natural gas and its processing for hydrogen.

How to extend

Use this link to hypothesize that 'gasification' (though often applied to coal/biomass) is sometimes referenced in the context of natural-gas feedstocks/processing and so search natural-gas technology sections for the term.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > v) Pyrolysis > p. 86
Strength: 3/5
“It is a process of combustion in absence of oxygen or the material burnt under controlled atmosphere of oxygen. It is an alternative to incineration. The gas and liquid thus obtained can be used as fuels. Pyrolysis of carbonaceous wastes like firewood, coconut, palm waste, corn combs, cashew shell, rice husk paddy straw and saw dust, yields charcoai along with products like tar, methyl alcohol, acetic acid, acetone and a fuel gas.”
Why relevant

Further describes pyrolysis as combustion/thermal processing of carbonaceous wastes that yields combustible gases and liquids, reinforcing the pattern of pyrolysis as a gas-producing technology.

How to extend

A student could contrast the feedstocks (waste/biomass) and outputs (syngas) here with conventional natural-gas extraction to judge whether these terms belong to extraction vs. alternative gas production.

Statement 3
Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of hydrogen fuel-based automobiles?
Origin: Web / Current Affairs Fairness: CA heavy Web-answerable

Web source
Presence: 1/5
"Thermal treatment including pyrolysis, gasification, incineration, and plasma gasification is the most commonly employed technique for the generation of energy in different forms and waste-to-wealth"
Why this source?
  • Directly mentions both 'pyrolysis' and 'plasma gasification' together as thermal waste-to-energy techniques.
  • Passage frames these terms in the context of waste/energy generation, not hydrogen fuel-based automobiles (no automobile context present).
Web source
Presence: 1/5
"Pyrolysis is a process that breaks down waste materials through heat without the presence of air, resulting in recyclable products such as char, oil, wax, and flammable gases"
Why this source?
  • Defines 'Pyrolysis' as a waste-to-energy process that transforms municipal solid waste into fuel/products.
  • Discussion is about waste management and energy production — it does not mention automobiles or hydrogen fuel-based vehicles.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Pyrolysis/Ga*ification > p. 293
Strength: 5/5
“Pyrolysis is a process of chemical decomposition of organic matter brought about by heat. In this process, the organic material is heated in the absence of air until the molecules thermally break down to become a gas comprising smaller molecules (known collectively as syngas). Gaeificatiorl can also take place as a result of partial combustion of organic matter in the presence of a restricted quantity of oxygen or air. The gas so produced is known as producer gas. The gases produced by pyrolysis mainly comprise carbon monoxide (z5olo), hydrogen and hydrocarbons (r5Yo), and carbon dioxide and nitrogen (6o70). The next step is to'clean'the syngas or producer gas.”
Why relevant

Defines pyrolysis as producing a syngas that 'mainly comprise(s) ... hydrogen' — links pyrolysis to hydrogen-bearing gas streams.

How to extend

A student could infer that technologies producing hydrogen-rich syngas (like pyrolysis) might be discussed when considering hydrogen supply for fuel-cell vehicles and check automobile chapters for cross-references.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Types Of Hydrogen Based On Extraction Methods > p. 298
Strength: 5/5
“zz,to,z, Types Of Hydrogen Based On Extraction Methods Depending on the nature of its extraction, hydrogen is categorized into three categories, namely, grey, blue and green. • Grey Hydrogen: it is produced via coal or lignite gasification {black orbrown}, or via a process called steam methane reformation (SMR) of natural gas or methane (grey). These tend to be mostly carbon-intensive processes. • Blue Hydrogen: It is produced via natural gas or coal gasification combined with carbon capture. storage (CCS) or carbon capture use (CCU) technologies to reduce carbon emissions. . Green Hydrogen: It is produced using electrolysis of water with electricity generated by renewable energy.”
Why relevant

Lists gasification (coal/lignite gasification) explicitly as a method used to produce hydrogen (grey/blue hydrogen categories).

How to extend

Use the rule that gasification is a hydrogen-production route to look for mentions of gasification variants (including plasma gasification) in sections on hydrogen for transport.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > v) Pyrolysis > p. 86
Strength: 4/5
“It is a process of combustion in absence of oxygen or the material burnt under controlled atmosphere of oxygen. It is an alternative to incineration. The gas and liquid thus obtained can be used as fuels. Pyrolysis of carbonaceous wastes like firewood, coconut, palm waste, corn combs, cashew shell, rice husk paddy straw and saw dust, yields charcoai along with products like tar, methyl alcohol, acetic acid, acetone and a fuel gas.”
Why relevant

States pyrolysis yields combustible gases and other fuels from biomass/wastes — showing pyrolysis is treated as a fuel-production route.

How to extend

Combine this with knowledge that hydrogen is a transport fuel to check whether pyrolysis-based hydrogen production is linked to vehicle fuel discussions.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.8 WASTE TO ENERGY > p. 294
Strength: 4/5
“In today's era, there are increasing quantities of waste due to urbanization, industrialization and changes in life patterns which are harmful to the environment. In the recent past, development of technology has helped to reduce the amount of waste for its safe disposal and to generate electricity from it. Waste-to-energy has the potential to divert waste from landfills and generate clean power without the emission of harmful greenhouse gases. This significantly reduces the volume of waste that needs to be disposed of and can generate power Pyrolysis and gasification are emerging technologies apart from the common incineration and biomethanation.”
Why relevant

Mentions pyrolysis and gasification as emerging waste-to-energy technologies, framing them as routes to generate fuel/power.

How to extend

A student could extend this by asking whether waste-to-energy hydrogen (via gasification/pyrolysis) is referenced in the book's sections on hydrogen mobility or fuel-cell vehicles.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Fuel cells for automobile transport > p. 296
Strength: 4/5
“0 Compared to vehicles powered by the internal combustion engine, fuel-cell-powered vehicles have very high energy conversion efficiency, and near-zero pollution, CO extsubscript{2} and water vapor being the only emissions. Fuel-cell-powered EV's (electric vehicles) score over battery-operated EV's in terms of increased efficiency and easier and faster refueling. In India, diesel-run buses are a major means of transport and these emit significant quantities of SPM and SOz. Thus, fuel-cell-powered buses and electric vehicles could be introduced with relative ease to dramatically reduce urban air pollution and to make a positive impact on urban air quality.”
Why relevant

Describes fuel-cell-powered vehicles as hydrogen-based transport technology, establishing the topic area where hydrogen production methods might be cited.

How to extend

Knowing fuel cells are the target application, a student could check whether production methods (pyrolysis/gasification/plasma gasification) are mentioned in that same context.

Statement 4
Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of waste-to-energy technologies?
Origin: Web / Current Affairs Fairness: CA heavy Web-answerable

Web source
Presence: 5/5
"## 2 Waste-to-energy techniques ### 2.1 Pyrolysis Pyrolysis is a process that breaks down waste materials through heat without the presence of air, resulting in recyclable products such as char, oil, wax, and flammable gases"
Why this source?
  • Directly labels a subsection under 'Waste-to-energy techniques' as '2.1 Pyrolysis'.
  • Defines pyrolysis in the context of transforming municipal solid waste into fuel and other products.
Web source
Presence: 4/5
"Gasification, Pyrolysis & Plasma Incineration What are waste gasification, pyrolysis, and plasma treatment/disposal technologies? Gasification, Pyrolysis and Plasma technologies heat waste materials to high temperatures, creating gas, solid and liquid residues."
Why this source?
  • Discusses 'Gasification, Pyrolysis & Plasma Incineration' explicitly as waste treatment technologies.
  • Describes gasification, pyrolysis and plasma technologies heating waste to high temperatures to create gaseous, solid and liquid residues—placing 'plasma' in the WTE context.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.8 WASTE TO ENERGY > p. 294
Strength: 5/5
“In today's era, there are increasing quantities of waste due to urbanization, industrialization and changes in life patterns which are harmful to the environment. In the recent past, development of technology has helped to reduce the amount of waste for its safe disposal and to generate electricity from it. Waste-to-energy has the potential to divert waste from landfills and generate clean power without the emission of harmful greenhouse gases. This significantly reduces the volume of waste that needs to be disposed of and can generate power Pyrolysis and gasification are emerging technologies apart from the common incineration and biomethanation.”
Why relevant

Explicitly lists 'Pyrolysis and gasification' as emerging technologies apart from incineration and biomethanation in a waste-to-energy discussion.

How to extend

A student could take this as evidence that pyrolysis/gasification are recognized waste-to-energy methods and then check whether any gasification variants (e.g., plasma-assisted) are discussed elsewhere.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Pyrolysis/Ga*ification > p. 293
Strength: 5/5
“Pyrolysis is a process of chemical decomposition of organic matter brought about by heat. In this process, the organic material is heated in the absence of air until the molecules thermally break down to become a gas comprising smaller molecules (known collectively as syngas). Gaeificatiorl can also take place as a result of partial combustion of organic matter in the presence of a restricted quantity of oxygen or air. The gas so produced is known as producer gas. The gases produced by pyrolysis mainly comprise carbon monoxide (z5olo), hydrogen and hydrocarbons (r5Yo), and carbon dioxide and nitrogen (6o70). The next step is to'clean'the syngas or producer gas.”
Why relevant

Provides a technical definition of pyrolysis and describes gasification/producer-gas production, linking both processes to conversion of organic/waste material into syngas.

How to extend

Using this definition, a student could infer that more advanced gasification techniques (such as plasma gasification) would be conceptually related and so search texts for 'plasma' + 'gasification'.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > v) Pyrolysis > p. 86
Strength: 4/5
“It is a process of combustion in absence of oxygen or the material burnt under controlled atmosphere of oxygen. It is an alternative to incineration. The gas and liquid thus obtained can be used as fuels. Pyrolysis of carbonaceous wastes like firewood, coconut, palm waste, corn combs, cashew shell, rice husk paddy straw and saw dust, yields charcoai along with products like tar, methyl alcohol, acetic acid, acetone and a fuel gas.”
Why relevant

Defines pyrolysis as combustion in absence of oxygen and describes its products when applied to carbonaceous wastes, reinforcing pyrolysis as a waste treatment/energy route.

How to extend

This supports treating pyrolysis as a clearly established waste-to-energy process; a student could therefore treat any omission of 'plasma gasification' as notable and seek specialized sources for that variant.

Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 6: Environmental Degradation and Management > Solid Waste > p. 44
Strength: 4/5
“Te solid waste may be safely disposed of in the following ways: (i) open dumps, (ii) landflls, (iii) sanitary land flls, (iv) Incineration plants, (v) composting, (vi) vermiculture or earthworms farming, (vii) bioremediation or the use of micro-organisms (bacteria and fungi) to degrade the environmental contaminants into less toxic forms, and (viii) pyrolysis – a process of combustion in the absence of oxygen.”
Why relevant

Lists pyrolysis among safe disposal/disposal-treatment options for solid waste, grouping it with other recognized waste-management technologies.

How to extend

A student can use this list-pattern to judge that pyrolysis is commonly included in waste-to-energy/management inventories, and then compare such inventories for mention of 'plasma gasification'.

Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.6 BIOMASS > p. 292
Strength: 3/5
“Biomass, on the other hand, releases carbon dioxide that is largely balanced by the carbon dioxide captured in its own growth (depending how much energy was used to grow, harvest, and process the fuel) Chemical processes like gasification, combustion and pyrolysis convert biomass to useful products. Combustion being the most common of them. Each of the technologies mentioned produces a major calorific end product and a mixture of by-products. The processing method is selected on the basis of nature.”
Why relevant

Notes that chemical processes like gasification, combustion and pyrolysis convert biomass to useful products, showing gasification and pyrolysis are mainstream conversion methods.

How to extend

From this general rule, a student could reasonably treat any variant of gasification (including plasma-based) as a subtype to look for in more specialised sections or texts.

Pattern takeaway: UPSC frequently pairs a 'Static Term' (Pyrolysis) with a 'Current Affairs Term' (Plasma Gasification). If you know the static term's context, you can ignore the complex one. The pattern is 'Term Association'—identifying the sector (Waste) rather than the mechanism.
How you should have studied
  1. [THE VERDICT]: Sitter. Directly solvable from Shankar IAS (Chapter 22: Renewable Energy / Waste to Energy) or any standard text covering Solid Waste Management.
  2. [THE CONCEPTUAL TRIGGER]: Waste-to-Energy (WTE) Technologies & Solid Waste Management Rules.
  3. [THE HORIZONTAL EXPANSION]: Memorize the Thermal Treatment Spectrum: Incineration (Excess O2, produces Heat), Gasification (Limited O2, produces Syngas [CO+H2]), Pyrolysis (Zero O2, produces Bio-oil/Char), Torrefaction (Mild pyrolysis for biomass), Biomethanation (Anaerobic digestion).
  4. [THE STRATEGIC METACOGNITION]: When studying 'Pollution' or 'Renewable Energy', create a simple table: Process Name → Input Material → Output Product. UPSC asks for the 'Context' (Application Domain), not the chemical engineering formula.
Concept hooks from this question
📌 Adjacent topic to master
S1
👉 Pyrolysis and Gasification as Waste-to-Energy Technologies
💡 The insight

Pyrolysis and gasification are described as emerging waste-to-energy processes used to convert biomass and urban/industrial waste into fuels and syngas.

High-yield for Environment and Energy topics: these processes appear in questions on waste management, renewable energy and sustainable urban policy. Understanding their differences (absence vs limited oxygen, products like syngas/char) helps answer questions on technology choices, emissions and circular economy strategies.

📚 Reading List :
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.8 WASTE TO ENERGY > p. 294
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Pyrolysis/Ga*ification > p. 293
🔗 Anchor: "Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of ..."
📌 Adjacent topic to master
S1
👉 Plasma (ionised gas) as a fundamental state of matter
💡 The insight

Plasma is the ionised state of gas exemplified by lightning and neon lights and underpins advanced high-temperature processing concepts.

Useful for technology and environment questions involving high-temperature treatments (e.g., plasma-based processing or thermal treatment). Grasping what plasma is allows candidates to evaluate feasibility and energy-intensity of novel industrial processes and link to industrial applications or hazards.

📚 Reading List :
  • Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 2: The Solar System > Plasma > p. 24
🔗 Anchor: "Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of ..."
📌 Adjacent topic to master
S1
👉 Rare earth extraction from monazite sands and thorium as a by-product
💡 The insight

Extraction of rare earths from monazite sands generates thorium as a by-product, linking mineral extraction to nuclear fuel considerations.

Directly relevant to resources, strategic minerals and nuclear fuel cycle topics in UPSC: helps answer questions on mineral endowments, processing externalities (radioactive by-products), and policy on strategic mineral management and reactor fuel strategies.

📚 Reading List :
  • Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 9: Distribution of World Natural Resources > thorium > p. 40
🔗 Anchor: "Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of ..."
📌 Adjacent topic to master
S2
👉 Pyrolysis and gasification as waste-to-energy processes
💡 The insight

Pyrolysis and gasification are thermochemical routes used to convert biomass and municipal waste into syngas or producer gas.

High-yield for environment and energy sections: these concepts explain technological options for waste management, decentralized energy and low-carbon fuels; they connect to topics on renewable energy deployment, pollution control and circular economy and enable questions on comparative advantages of waste-to-energy methods.

📚 Reading List :
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Pyrolysis/Ga*ification > p. 293
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > 22.8 WASTE TO ENERGY > p. 294
🔗 Anchor: "Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of ..."
📌 Adjacent topic to master
S2
👉 Steam Methane Reforming (SMR) and hydrogen classification
💡 The insight

SMR of natural gas is a principal method for hydrogen production and underpins the classification of hydrogen as grey or blue depending on CCS.

Crucial for questions on the hydrogen economy and decarbonisation: mastering SMR links natural gas use to hydrogen policy, carbon capture strategies and energy transition narratives, enabling analysis of trade-offs between hydrogen production routes.

📚 Reading List :
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Types Of Hydrogen Based On Extraction Methods > p. 298
🔗 Anchor: "Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of ..."
📌 Adjacent topic to master
S2
👉 Major uses and distribution of natural gas
💡 The insight

Natural gas is widely used for power generation, fertiliser manufacture, industry and as transport/cooking fuel, with specific regional reserves in India.

Core for economy and geography: understanding natural gas consumption patterns, reserve locations and import dependence informs questions on energy security, infrastructure and resource policy; connects to industrial policy and regional development issues.

📚 Reading List :
  • Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 9: Distribution of World Natural Resources > natural gas as a Resource > p. 15
  • NCERT. (2022). Contemporary India II: Textbook in Geography for Class X (Revised ed.). NCERT. > Chapter 5: Print Culture and the Modern World > Natural Gas > p. 115
  • Indian Economy, Nitin Singhania .(ed 2nd 2021-22) > Chapter 15: Infrastructure > Natural Gas > p. 447
🔗 Anchor: "Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of ..."
📌 Adjacent topic to master
S3
👉 Gasification as a hydrogen production route
💡 The insight

Gasification of coal or lignite is a listed method for producing hydrogen, which underpins discussions of hydrogen supply for energy uses.

High-yield for questions on the hydrogen economy and energy transition: it explains types of hydrogen (grey/blue/green), links to emissions implications and policy choices, and connects to national missions on green hydrogen.

📚 Reading List :
  • Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 22: Renewable Energy > Types Of Hydrogen Based On Extraction Methods > p. 298
  • Indian Economy, Nitin Singhania .(ed 2nd 2021-22) > Chapter 21: Sustainable Development and Climate Change > National Hydrogen Energy Mission (NHM) - announced in Union Budget 2021-22 > p. 605
🔗 Anchor: "Are the terms "pyrolysis" and "plasma gasification" mentioned in the context of ..."
🌑 The Hidden Trap

Torrefaction. It is a 'mild' form of pyrolysis (200-300°C) used to convert biomass into a coal-like material (bio-coal) with higher energy density. Expect this term in future WTE questions.

⚡ Elimination Cheat Code

Etymology Hack: 'Pyro' = Fire/Heat, 'Lysis' = Breakdown. 'Gasification' = Making gas. You need a complex solid to break down into gas using heat. Natural Gas (B) is already gas. Hydrogen Autos (C) consume fuel, they don't carry industrial thermal reactors. Rare Earths (A) involves chemical separation/leaching. Only Waste (D) is a complex solid that needs heat to break down.

🔗 Mains Connection

Links to GS-3 Infrastructure (Energy) and GS-3 Environment (Pollution). Specifically, the 'Gobardhan Scheme' (Waste to Wealth) and the 'Circular Economy' push in the Union Budget. WTE is the bridge between urban sanitation and energy security.

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SIMILAR QUESTIONS

IAS · 2022 · Q65 Relevance score: -2.59

Which one of the following is the context in which the term "qubit" is mentioned ?

IAS · 2012 · Q37 Relevance score: -5.11

Biomass gasification is considered to be one of the sustainable solutions to the power crisis in India. In this context, which of the following statement is/are correct? 1. Coconut shells, groundnut shells and rice husk can be used in biomass gasification. 2. The combustible gases generated from biomass gasification consist of hydrogen and carbon dioxide only. 3. The combustible gases generated from biomass gasification can be used for direct heat generation but not in internal combustion engines. Select the correct answer using the codes given below:

IAS · 2020 · Q43 Relevance score: -7.05

The term 'West Texas Intermediate', sometimes found in news, refers to a grade of

IAS · 2024 · Q39 Relevance score: -7.10

"Membrane Bioreactors" are often discussed in the context of :

IAS · 2025 · Q45 Relevance score: -7.18

Consider the following substances: 1. Ethanol 2. Nitroglycerine 3. Urea Coal gasification technology can be used in the production of how many of them?